Calculator



June 2, 1942. F. A. WARDENBURG ET AL 2,284,701

CALCULATOR Filed Aug.4 2, 1959 3 Sheets-Sheet 1 Frederick .War denhINVENTORS um Ralph LIIU QBEYW /WRNEY June 2, 1942.

F. A. WARDENBURG ET Al.

4 CMJGULATOR Filed Aug. 2, 1939 3 Sheets-Sheet 2 MIMI PIN UP 77u Flrruur. mi' In traan/t WM5 rmt una,

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INVENTORS Rhum June 2, 1942 F. A. WARDENBURG E-r A1. 2,284,701

CALCULATOR Filed Aug'. 2, 1939 3 Sheets-Sheet 3 INVENTORS Frederick.Wardenbur |g Ralph 14.251522 ma @M ATTOR Y Patented .lune 2, 1942CALCULATOR Frederic A. Wardenburg and Ralph L. Dodge, Wilmington, Del.

Application August 2, 1939, Serial No. 287,880

2 Claims.

lIhis invention relates to calculators for rapid and accuratedetermination of the time oi occurrence of various natural phenomena,which regularly manifest themselves at definitely predeterminable times,such as tides, tidal currents, rising and setting of the sun, moon orstars.

Although the time schedules of these phenomena at specified referencepoints on the earths surface are published in advance by agencies or theUnited States Government and by agencies of the governments of othercountries, the customary arrangement of these data in tabular form doesnot lend itself readily to rapid and convenient selection for otherpoints than the tabulated reference points.

It is an object of this invention to overcome the disadvantages outlinedand to provide a calculator which presents in compact form the datarelating to a single phenomenon over a definite period of time and for amultiplicity of points on the surface of the earth. Our novelarrangement permits rapid calculation of the correct time of occurrenceof a phenomenon for selected locations and dates.

Other objects and the basis of construction of the calculators as wellas the advantages oi the arrangement thereof will become apparent from aconsideration of the description following, taken in connection with theaccompanying drawings illustrating the complete calculator, Fig. l, andits two component parts, the front, or placej disk, Fig. 2, and theback, or time disk, Fig. 3. For purposes of illustration and because ofits preferred usage therefor we have deliberately restricted ourdescription and illustration to a tide calculator, but it will beevident to one skilled in the art that calculators for other phenomena,the times of which can be predetermined with certainty, are alsosusceptible to construction by the same principle, and our descriptiondoes not limit our invention to the tide calculator herein described.

Each calculator consists of two circular disks of suitable materials,such as Plastacelej cardboard, wood, etc., of such relative dimensionsthat when one of the disks is superimposed concentrically on the other,the edge of the back disk, Fig. 3 will extend beyond the edge of thefront disk, Fig. 2, for some convenient distance, preferably, but notnecessarily, one-half inch.

The peripheral portion 1 of the back disk, which is thus exposed aroundthe outside of the front disk, is divided arcuately by radial markingsinto equal intervals, representing intervals of time. The total numberof equal divisions around the ring l must be at least equal to thenumber of hours of the civil day in which the phenomenon for which thecalculator is being constructed is known to occur. For the sake ofprecision in calculation, the number of divisions may exceed thisminimum. In the case of the tide calculator, the number of equaldivision in the time ring must be at lea-st twentyfour, since the tidalphenomenon may manifest itself by highs and lows at any time or" thetwenty-four hours of the civil day. The time ring I of the tidecalculator, may be further subdivided, for convenience, into equal timeintervals, representing single or multiple minute intervals. In theaccompanying illustrations, Figs. l and 3, the time ring l is dividedinto twenty-four equal hourly intervals, and each hour interval isfurther subdivided into twelve equal ve minute intervals. The hourlymarkings are numbered in consecutive order, preferably in accordancewith the customary time system, for example, from l2 midnight through 1a. m., 2 a. In., etc., to l2 noon, and continuing from l2 noon through lp. m., 2 p. m., etc., to l2 midnight. The numbering 0 (midnight) to 23could be employed without departing from the spirit of our invention.

If the phenomenon for which the calculator is being constructed wereknown to occur only between definite limiting hours of the civil day,like the rising of the sun, the time ring, or a portion thereof, may bedivided into a number of equal hourly intervals corresponding to thenumber of hours between the earliest rising and latest rising, thusobtaining the longest possible unit time arc for any given mean diameterof time ring, a desirable, but not required, feature of the calculator.

The area of the back disk, inside the time ring, is divided into anumber of inner rings 2 each concentric with the time ring I.

Each inner ring contains a series of numbers representing dates, sospaced around the inner rings that when any single date is disclosedcentered in a date hole 3 of the concentrically superimposed front disk,Fig. 2, the arbitrarily located reference index 4 on the front disk willpoint to the time on the time ring l at which the phenomenon will occurat the reference place on the date appearing centered in the date hole.

On the drawings, illustrating the place disk (Fig. 2), the date holesare represented by small four-sided black areas 3. For convenience inuse, the date holes are arranged in columns, one column for each aspectof the phenomenon for which the calculator is being constructed. In thecase of the tide calculator, one column 5 contains the .date holes forhigh tide and the yother column E contains the date holes for loW tide.This columnar arrangement 0f holes is an advantageous and preferred butnot absolutely necessary feature of Vour invention. ,The radialdistances of the date'holes from the axis 'l of the calculator mustcorrespond to the radii of the respective date rings on the time disk.

Each date hole may carry, on an extension of its arc, a designation 8 ofthe month and days thereof that appear on Ythe corresponding date ring.This designation is also an advantageous and preferred but notabsolutely necessary re-V quirement of our invention.

The arbitrarily located reference index d is drawn as a radius, to thecircumference of the front disk and is labeled by the name of thegeographic reference point for which the data have been predetermined.Other indicia for subordinate' geographic points 9 are drawn radially onthe front disk at angular distances from the reference index equal,respectively, to the predetermined time Vintervals between theoccurrence of the phenomenon at the geographic reference point and itsoccurrence at the subordinate geographic points. The` number ofsubordinate points that can be included on a single calculator islimited only by the legibility of the namesand the availability of thetime interval data. The indicia for subordinate Ystations at which thetime of occurrence is later than at the reference station must be on theside of the reference index corresponding to a later time on the timering I and similarly the indicia for subordinate stations at which thetime of occurrence is earlier than'at the reference station must be onthe side ofthe reference index corresponding to an earlier time on thetime ring I.

For convenience in use the two disks, which together constitute acalculator', are fastened together by a pivot at the center l of the twodisks, so that the front disk can be rotated concentrically relative 'tothe back disk. If it is desired to representV on a single calculator twophenomena, the two time-date disks can be `drawn or printed on the twosides of a single of the three disks,` so that the three disks can be'rotated concentricallyV relative to one another.

Although the calculator illustrated herein,

Fig. 1, is deliberately constructed to cover a pe- Y i adjustment, saidback disk having a ring adjacent to the periphery and projecting beyondthe front disk and being divided arcuately into equal, consecutivelylabeled intervals representing time; said back disk having in addition aseries of concentric inner rings, each inner ring bearing numbersrepresenting dates; said front disk being Yperforated by holes'whoseradial distances from the center of they front disk are, respectively,equal to the radial distances of the inner rings from the' center of theback disk and which are adapted to disclose, through the holes,successively, by rotation, the dates in the corresponding inner rings ofthe back disk; said front disk bearing in addition, radial indiciaterminating at the circumference of said front disk and being spacedarcuately to represent tidal time intervals between geographiclocations; said indicia being so located with respect to the holesthat'thel indicia willV point to the times on the time ring ofthe backdisk at which a tidal phenomenon f will occur at the respectivegeographical locations riod from May 1, 1939 to September 30, 1939, Y'

inclusive, it will be apparent that a longer or` shorter period can becovered on a single calculator by increasing the number of inner ringsand daterholes or by including a longer interval on each date ring,without departing from the on the date appearing centered in anydatehole.

2. A calculator adapted by spatial arrangement to show precalculablerelationships between time, date, place and appearance of specificphenomena, comprising front and back circular disks, arrangedconcentrically in a superimposed order and adapted to permit relativerotative adjustment, said back disk having a ring ad-V jacent to theperiphery and projecting beyond the front disk and being dividedarcuately into equal, consecutively labeled intervals representing time;said back disk having in addition a series of concentric inner rings,each inner ringY bearing numbers representing dates; said front diskbeing perforated by holes Whose radial distances from the center of thefront disk are, re-

spectively, equal to the radial distances of the inner rings from thecenter of the back disk and and which are adaptedV to disclose, throughthek holes, successively, by rotation, the dates in theV correspondinginner rings of the back disk; said iront disk bearing in addition,radial indicia terminatingat the circumference of said front disk spiritof our invention. A calculator for an entirely different period can beconstructed 0n the saine principle as the calculator illustrated byproperly selecting the'relative arcuate locations of the indicia, dateholes and dates.

The construction of the calculator, as described herein lends itself tothe convenient presentation of data on other phenomen such as and beingspaced accurately to represent time intervals between the appearance ofa celestially determined natural event at different geographicallocations, said indicia being soY located with respect to the holesthatI the indicia will pointy to the times on the time ring of the backdisk to which the celestiallydetermined natural. event will occur at therespective geographical locations on the data appearing centered in anydate hole;

FREDERIC' A. WARDENBURG. RALPH L. DODGE..

